Reverse Charge - Supplier Services Invoice

Hope someone can help.

We have received an £ invoice from a supplier who is VAT registered and who is RCT (Relevant Contracts Tax - Ireland) registered at 20%.  On the invoice it says VAT on this supply to be accounted for by the principle contractor

we are the principle contractor.

What "T" code is to be used as there is no VAT on the supplier's invoice.